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Journal ArticleDOI

Case study of intense scintillation events on the OTS path

P. Basili, +4 more
- 01 Jan 1990 - 
- Vol. 38, Iss: 1, pp 107-113
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TLDR
In this paper, the statistical properties of the beacon signals together with their correlation with the concurrent radiometric signal suggest that both scintillation and a variable attenuation mechanism act to produce the field fluctuations.
Abstract: 
Selected events of enhanced field amplitude fluctuations recorded on the Orbital Test Satellite (OTS) path have been analyzed. The statistical properties of the beacon signals together with their correlation with the concurrent radiometric signal suggest that both scintillation and a variable attenuation mechanism act to produce the field fluctuations. Analysis of the coherence between the beacon and the radiometric signals gives an indication of the fluctuation frequency range over which each effect prevails. The comparison between scintillation data collected by a large (17 m) and a small (3 m) antenna indicates that the turbulence of the refractive index was particularly high during the course of the considered events. >

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Citations
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Patent

Wireless local area network (WLAN) technology and applications including techniques of universal frequency translation

David F. Sorrells, +6 more
TL;DR: Frequency translation and applications of same are described in this paper, including wireless local area network (WLAN) applications such as IEEE Standard 802.11 WLANs, such as, but are not limited to, frequency down-conversion, frequency up-concversion, enhanced signal reception, unified downconversion and filtering, and combinations of same.
Patent

Method and system for down-converting an electromagnetic signal

David F. Sorrells, +6 more
TL;DR: In this paper, the authors proposed a method for down converting a modulated carrier signal to a demodulated baseband signal, which requires that at least some of the energy stored in the first storage device is discharged when the first switch is off.
Patent

Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same

David F. Sorrells, +6 more
TL;DR: In this paper, the authors described a system for down-converting and up-concussing an EM signal by recursively operating on approximate half cycles (½, 1½, 2½, etc.) of the carrier signal.
Patent

Method and system for ensuring reception of a communications signal

Michael J. Bultman, +4 more
TL;DR: In this article, a modulating baseband signal with desired information is accepted, and a plurality of redundant spectrums is generated, each redundant spectrum comprises the necessary amplitude, phase, and frequency information to substantially reconstruct the modulating BS signal.
Patent

Method and apparatus for reducing DC offsets in a communication system

Gregory S. Rawlins, +3 more
TL;DR: In this paper, a feedback loop circuit reduces DC offset in a wireless local area network (WLAN) receiver channel and a circuit provides gain control in a WLAN receiver channel.
References
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Book

Radar reflectivity of land and sea

Maurice W. Long
TL;DR: In this paper, the Earth and its effects on radar are discussed, including the effects of surface roughness on Forward-Scattered Fields on radar reflectivity and the effect of the Earth's surface on radar.
Journal ArticleDOI

Aperture Averaging of Scintillation

David L. Fried
- 01 Feb 1967 - 
TL;DR: In this article, the relationship between the statistics of log-amplitude fluctuations and irradiance fluctuations due to atmospheric turbulence is derived and the effect of use of a large aperture diameter in reducing the variance of a fluctuating signal is evaluated.
Journal ArticleDOI

Scattering induced microwave scintillations from clear air and rain on earth space paths and the influence of antenna aperture

J. Haddon, +1 more
- 01 May 1986 - 
TL;DR: In this article, the variance and spectrum of amplitude scintillations due to scattering in both turbulent clear air and rain, are investigated and the important aspect of antenna aperture smoothing with special emphasis on earth-space paths and the equations derived are applicable to system design and remote sensing.
Journal ArticleDOI

Experimental and theoretical statistics of microwave amplitude scintillations on satellite down-links

T. J. Moulsley, +1 more
- 01 Nov 1982 - 
TL;DR: In this paper, the statistics of scintillation intensity on an X-band satellite downlink obtained using the orbital test satellite beacon transmissions were analyzed and the experimentally found distribution is shown to depart significantly from the expected log-normal distribution, and this is explained in terms of a Gaussian process with a time variable standard deviation from which a universal model is derived.
Journal ArticleDOI

Measurement and modeling of scintillation intensity to estimate turbulence parameters in an Earth-space path

E. Vilar, +1 more
- 01 Apr 1984 - 
TL;DR: In this paper, the theoretical and experimental aspects of the analysis of amplitude scintillations as a possible remote-sensing tool of atmospheric turbulence parameters with special emphasis on earth-space paths are explored.